Striking tool



E. G. HYSING STRIKING TOOL May 3, 1932.

Filed Jan. 7, 1929 Patented May 3, 1932 IUNITED STATES PATENT l OFFICEE'RIK GUSTAF HYSNG, 0F STOCKHOLM, SWEDEN, `ASSIGNOR TO AKTIEBO'LAGETNOR- DISKA ARMATURFABRIKERNA, OF STOCKHOLM, VSVVEIIEIV, A LIMITED COMPANY STBIK'ING rrooL Application med January 7, 1929, Serial No.330,841, and in Sweden .Tanuary 7, 1928,.

Thepresent invention relates to an arrangement in striking tools of thekind, which consists partly of a suitable power rotated striking body,mounted to slide axially and provided with one or more oblique strikingfaces, which cooperate with corresponding oblique faces located on ananvil and give the striking body a recoil movement, and partly of devicecooperating with the striking body by which the latter is caused to movetowards the anvil following its recoil movement.

The invention is essentially characterized by the fact, that thestriking body consists of or is provided with one ormore balls, the

faces of which form the oblique striking faces of the striking body.

Other characteristic features of the inventionrwill be more clearly setforth hereinafter. In the annexed drawings:

Fig. 1 shows a longitudinal section of a striking tool constructedaccording to this invention, and Fig. 2 is a section on the line II-IIin Fig. l. Fig. 3 shows a longitudinal section of the lower part of astriking tool, according to another embodiment, and Fig.

4 illustrates a third embodiment, also in longitudinal section. Fig. 5is a section yon the line V-V in Fig. 4. Fig. 6 is a fragmentary sectionon the line VI-VI of Fig. 7 of afourth embodiment and Fig. 7 is an endview of a det-ail in Fig. 6.

Referring to the embodiment according to Fig. 1, 1 is a sleeve mountedto turn in the bearing 2 of the frame 10. This sleeve l may be rotatedby means of an electric motor .3() or the like. A shaft?) is arranged toturn and slide in said sleeve. The front part of this shaft 3 is giventhe shape of a holder 4 for a pair of balls 5, which balls are arrangedin this holder in such a way, that they are forced to follow therotation as well as in the reciprocating movement of said holder.Besides they are free to move in a radial direction. For this purposethe holder 4 is provided with a recess 6 of a width corresponding aboutto the diameter of the balls. Said recess is so constructed that aportion lof the circumferenceof the balls 5 extends forwards fromtheholder to allowy the balls to make 50 contact with a pair of obliquefaces 7, located on the anvil 9 sliding in the frame bearing 8. Asobvious from Figs. l and 2, the sleeve 1 has its front end enlarged andof a cross section almost oval, so that its interior width correspondsabout to the width of the holder 4. Besides, the open front portion ofthe sleeve or that portion adjacent the anvil 9 is relatively wide andtwo opposite sides 11 thereof are inclined in rearwardly convergingrelationl as clearly shown in Fig. l. The sleeve isalso spiral shaped assuggested in Fig. 2. l

The arrangement worksin the following manner.

Assume that the parts occupy the position according to Fig. 1. In thisposition the holder 4 together with the balls 5 are moving in thedirection towardsY the anvil9, in order to deliver a blow thereon. Therotary movement of the sleeve 1 is transmitted to the balls 5 and, thus,also the shaft 3 and the holder 4 are forced to rotate. During rotationthe balls 5 will, in the striking moment, contact the oblique faces 7 onthe anvil and the vrecoil movement of the balls is-thus effected,bringing with them the holder 4 and the shaft 3. At this recoil movementthe balls 5 are simultaneously guided by the inclined sides 11 of thesleeve 1, and forced to move ina direction towards thev axis of rotationof the holder, overcoming the centrifugal force, generated by the ballsrotating about the shaft 3. When their recoil movement is stopped, theballs return tothe front position, shown in Fig. 1, moving along theinclined Walls 11 of the sleeve and again meets the anvil.

It is not intended that the holder 4 shall strike against the sleeve lat the end of the upward movement of the balls 5 and the holder 4.

kThe upward movement of the balls 5 and the holder 4 ceases before theholder 4 touchesthe inner end of the sleeve 1.

This stopping of the balls 5 and the holder V4 is effected by the factthat the motive energy of the balls and the holder is required forbringing the balls 5 radially towards the axis of rotation of the shaft3. This, namely, will require energy although this energy will graduallydecrease the nearer the balls 5 will come to this axis of rotation,assuming a constant speed of rotation.

The cooperation of the balls 5 and the oblique wall at the rejection ofthe balls in the direction away from the anvil 9 may, as to the mode ofoperation, be compared with a brake, the force of which graduallydecreases according as` the axial speed of movement of the balls willdecrease, 'so as in eiiect to provide means in the nature of an energystoring device. In all events by bringing the balls in the directiontowards the axis of rotation there will lbe givena possibility ofbringing the balls forward in the direction towards the anvil at a greatspeed by the infi'uen'ce of the `centrifugal force.

The spiral shape vof the sleeve is not necessary but a suitable choiceof the spiral shape for the sleeve in relation to the oblique faces 7,it will be possible to obtain a movement between the balls 5 and thesleeve 1, entirely free from shocks.

It is not necessary to use two 'balls but, for

instance, 3 lor 4 balls may be used in an arrangement according to Figs.1 and 2, without departing' from the principle of the invention in anyway.

It is also possible to use only one ball, in which case the constructionmay be simplified, the Iholder 4 being dispensed with, if desired. Anarrangement carried out in this way is shown in Fig. 3.

rThe sleeve 12 has in this case a vcylindrical cross section, but has anoblique position in relation to the axis of the power rotated shaft '13by means of which the sleeve is rotatably mounted in the bearing 14. Theinterior diameter of the sleeve corresponds 'to the diameter 'of theball 15. The ball 15 cooperates in the same manner as in the em'-bodi-ment according to Fig. 1, with oblique striking faces on the anvil9, mounted to slide in the bearing 8.

The arrangement works in the following manner: f

When the bally 15 has arrived at its outermost position, the blowaga-inst 5th-e anvil 9 isidelivered, after which the ball recoils guidedby the oblique sleeve 12. At this recoil movement, energy is stored aspreviously, s ince the ball 15 is forced, on account of the obliqueposition of the sleeve 12, to approach towards the axis of 'rotation ofthe shaft 13, Vag'ainstthe influence of the centrifugal force. The ball15 will thus be stopped and then moved forwards towards the anvil Aunderthe influence of centrifugal force.

Also in 4this case, the sleeve maybe :given a spiral shape or be vplacedin a correspondthe embodiment according to Figs. 4 and 5 has no shaftmounted to slide in the sleeve 1. Instead of it the holder 16 isprovided with a pair of projecting guiding fianges 17, running incorresponding grooves 18 in the sleeve 1. 1n the drawings the sleeve 1is straight and not spiral shaped as in the embodiment according toFig. 1. The sleeve according to Figs. 4 and 5, however, may if desiredbe given a spiral shape.

In this case the grooves 18 will also have a corresponding twist orturn.

The embodiment according to Figs. 6 and 7 shows 4a sleeve or body 19,provided with two cylindrical guides 20, 21 for the balls 22 and 23.rlhe working manner of the arrangement is similar to that one shown inFig. 3 and from Fig. 7 it is obvious that the guides 20, 21 are disposedobliquely tothe axis :of

rota-tion so as to obtain an energy fsto'rifn'g in the way, explainedabove in connection Vwith the other embodiments.

Having now vparticularly described the nature of my invention and themanner ofits operation, what 1 claim is t- 1. A striking tool includingIan anvil having at least one voblique impact surface, a

striking member rotatably and re'cilpro'cably mounted with respect tothe anvil 'and provided with at least fone striking face 'in the form ofa ball for coactifng 'with the impact surface in the `an'viil for'effecting a recoil movement of the member, the axis of rotation of saidstriking member substantially coinciding with the axis of the anvil, anda guiding and rotating device cooperating 'with the ball to cause thelatter to deliver bflows upon the anvil.

2. A strik-ing tool as claimed .in claim l,

wherein a plurality of balls are .provided 1"* and a common holder forYthe balls.

3. A striking tool vas claimed in claim 1 wherein a .plurality of ballsare provided, fa common holder in which the balls are 'arranged, theholder being 'slidably mounted i* in the guiding and Vrotating device.

4. A striking tool ias sclaimed in claim 1 wherein a plurality of ballsare .provided 'and the rotating device includes inclined guides arrangedin'such a way that the balls yduring i a 'recoil movement aremovedfcontr'ary to th'e direction of the `centrifugalforce acting uponthe balls.

5. A striking ftool as y'claimed 2in claim l vided, la common 'holderrotatably and slidably 'mounted in Said "rotating and guiding device. Y

6. A striking tool as claimed -in claim `1 wherein a plurality of vballsa're provided, '1" a holder for the balls, the vrotating and guidingdevice bei/ng spiral in relation Ito'the axis yof rotation andcooperating with-*the hails,

substantially as and for the purposes set forth.

7. A striking tool in accordance with claim l wherein the striking bodyand energy storing device include a plurality of balls, a holdertherefor, said rotating and guiding device being in the form of a Sleevefor slidably receiving the holder, the sleeve being substantiallyoval-shaped in cross section so asv to allow the balls to move onlyradially and axially therein, substantially as and for the purpose setforth. Y

8. In a striking or hammering tool, a striking member, an anvilengageable by the striking member, said striking member being mountedfor rotary and reciprocating movement, the axis of rotation of saidstriking member substantially coinfciding With the axis of the anvil, aball forming the striking face of the striking member and acting inresponse to centrifugal force developed incident to rotation of thestriking member to effectthe striking movement, and means acting inresponse to the impact of the ball upon the anvil to eect a recoilmovement of the striking member. Y

9. In a striking or hammering tool, a striking member, an anvilengageable by the striking member, said striking member including arotary guiding part, the axis of rotation of said striking membersubstantially coinciding with the axis of the anvil, and a reciprocatingpart mounted in the rotary guiding part so as to partake in the rotarymovement, said reciprocating part including a holder, and a plurality ofradially movable balls forming the striking face of the striking memberand Which act in response to centrifugal force developed incident torotation of the guiding part to effect striking movement of the strikingmember, the impact face of the anvil being provided With meanscooperating With the balls and the guiding part to effect a recoilmovement of the holder.

ERIK GUSTAF HYSING.

